Knife sharpener



May 1, 1956 w. R. SPAULDING 2,743,560

KNIFE SHARPENER Filed Feb. l5, 1954 United States Patent '0 2,743,560KNIFE SHARPENER William R. Spaulding', KausasCit Mo.

Application February 15,1954, Serin'l'No. 410,287

2 claims. (el. 's1- rim This invention relates to a new and improvedknife Sharpener, the primary object being to provide a readily portabledevice that may be either held in the hand, placed on a flat surface oranchored by use of suitable fasteners in a vertical or in a horizontalposition ready foruse.

lt is the most important object of the present invention to provide aknife Sharpener so designed as to permit a push-pull action of the knifeagainst a pair of spaced* apartrotatable grinding wheels to the end thatsuch grinding elements will wear evenly and, therefore, be long-lasting.

Another important object of the present invention is to provide a knifeSharpener wherein the grinding discs are held in spaced-apartrelationship on a rotatable shaft for reception of the knifetherebetween and thereby preventing contact of the sharp edge of theknife with the grinding elements themselves.

Other important objects include the way in which roller means areprovided as a` safety factor andto protect cutlery from marring orscratching; the way in which ratchet means, provided to limit rotationof the grinding discs to one direction, is so arranged as to lock thegrinding element assembly in place; the way in which the grindingelements are protected against breakage at all times; the manner inwhich important details of `construction permit reversal of the grindingelements thereby increasing the life thereof; and many oth-er more minorobjects all of which will be made clear as the following specificationprogresses.

In the drawing:

Figure l is a top plan view of a knife Sharpener made pursuant to mypresent invention.

Fig. 2 is a longitudinal, cross-sectional view taken on line ll-Il ofFig. l.

Fig.3 is an end elevational view thereof.

Fig. 4 is a transverse, cross-sectional view taken on line lV-lVof Fig.2; and

Fig. 5 is an enlarged, cross-sectional view taken on line V-V of Fig. 3showing the manner of sharpening a knife through use of the inventionforming the subject matter of this application.

The knife Sharpener illustrated in the drawing includes a supportbroadly designated by the numeral which includes a U-shaped bottom 12having upstanding flanges 14 and 16 at the ends thereof.`

Support 10 includes additionally, a pair of upstanding l sides 18 andZtlbetween the flanges 14 and 16 having out-turned flanges 18a and 20athroughout the lengths of their lowermost longitudinal edges and whichrest upon the bottom 12. Suitable fasteners 22 secure the anges 18a and20a to the bottom 12 and thereby hold the sides 18 and 20 in spacedparallelism.

An externally threaded shaft 24 spans the distance between the walls 18and 20 and is rotatably carried thereby. Shaft 24 in turn receives apair of grinding elements 26 held in spaced-apart relationship by spacer28 on the shaft 24. The grinding elements 26 are disposed between2,743,560 Patented May 1,1956

'ice

a pair of washers 3`0 on the shaft 424 and the grinding elements 26 areheld clamped against the spacer 28 by op-4 posed nuts 32 and 34 on theshaft 24. Nut 32 has a plurality of ratchet teeth 36 engaged by apan/1.38 swingably mounted on the side 18 by a pivot pin 4'0; A4 spring42,

hooked 'through an opening 44 in the `pawl 38 and looped.

the uppermost edges thereof and adjacent `one end of" the support 10',mounts a pair of guide :rollers 46 therebelow for rotation on verticalaxes 48. A roller S0 is carried by the sides 13 and 20 therebetween forrotation in parallelism with the axis of rotation orf shaft 24. TheSharpener may be mounted on a horizontal or a vertical supportingsurface if desired, through use of fasteners (not shown) in openings 52extending through flanges 13a and 20a and the bottom 12.

Alternately, the Sharpener may be held in the hand or against asupporting surface to sharpen a knife 54 in the manner illustrated byFig. 5 of the drawing. Knife 54 is inserted between the grindingelements 26 and a pushpull action will cause the elements 26 to rotatefreely in a clockwise direction (viewing Fig. 5) when the knife 54 ismoved in the direction of arrow 56. Such rotation of the shaft 24 andthe elements 26 thereon is permitted by the pawl 38 by virtue of theyielding in spring 42 as the teeth 36 ratchet past pawl 38.

When, however, the knife 54 is pulled in the opposite direction as shownby arrow 58 in Fig. 5, one of the teeth 36 will move into engagementwith the uppermost free end of the pawl 38 and the latter will therebyrestrain the shaft 24 and the elements 26 against retrograde rotationanti-clockwise viewing Fig. 5. Consequently, with the grinding elements26 held against such anti-clockwise rotation, pulling of the knife 54 inthe direction of arrow 58 will grind the opposed faces of the knife 54defining at their intersection the cutting edge thereof and sharpeningwill take place.

The roller S0 is disposed to receive the sharp edge of the knife 54 toprevent its coming into contact with any part of the support lllparticularly during sharpening of the point of knife 54, therebyavoiding; damage to the cutting edge of the knife 54.

The rollers 46 also prevent the knife 54 from being accidentally movedinto engagement with lany part of the support 10 and causing damage tothe knife 54 such as by scratching or marring.

The threads on the shaft 24 and in the nut 32 are such as to causetightening of the nut 32 against the proximal washer 30 whenever theknife 54 is pulled in the direction of arrow 5S and there is, therefore,assurance that eleelements on the Shaft for rotation therewith; meansholding the elements spacedapart for reception of a knife therebetween;ratchet means operably coupled with the shaft for restraining the sameagainst rotation in one direction; a pair of spaced guide rollers forthe knife; and means mounting the rollers above and for free rotation ona pair of corresponding parallel axes disposed to one Side of the axisof rotation of the shaft and perpendicularly to a plane through thelatter axis, said parallel axes being spaced in a direction parallel tosaid axis of rotation of the shaft to accomodate the knife between therollers. 2. A knife Sharpener comprising an elongated shaft; meansmounting the shaft for rotation on its longitudinal axis; a pair ofgrinding elements; means mounting the elements on the shaft for rotationtherewith; means holding the elements spaced-apart for reception of aknife therebetween; ratchet means operably coupled with the shaft forrestraining the same against rotation in one direction; a pair of spacedguide rollers for the knife; means mounting the rollers above and forfree rotation on a pair of corresponding parallel axes disposed to oneside of the axis of rotation of the shaft and perpendicularly to a planethrough the latter axis, said parallel axes being spaced in a directionparallel to said axis of rotation of the shaft to accommodate the knifebetween the rollers; a single guide roller for the knife disposed on theopposite side of said axis of the shaft; and means mounting the singleroller for rotation on an axis parallel with said axis of the shaft.

References Cited in the file of this patent UNITED STATES PATENTS

